This README is the one indexed from the repository at its latest ref, not from the tag for this version.

prettytable

Crystal library that makes it easy to build simple text tables.

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     prettytable:
       github: henrikac/prettytable

2. Run shards install

Usage

Basic example

require "prettytable"

# default initialize
# table = PrettyTable::Table.new
# table.set_headers(["id", "name", "age"])

# initialize + set_headers
table = PrettyTable::Table.new(["id", "name", "age"])

table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"]
]

puts table

will output

+----+-------------------+-----+
| id | name              | age |
+----+-------------------+-----+
|  1 | Melody Connolly   |  42 |
|  2 | Leslie Hutchinson |   1 |
|  3 | Codey French      |  58 |
+----+-------------------+-----+

Notes:

• Once headers has been set they cannot be re-set / updated.
• Rows cannot be added to the table before the headers has been set.

Ways to add rows to table

• #add_row(row : Array(String))
• #add_rows(rows : Array(Array(String)))
• #<<(row : Array(String))
• #<<(rows : Array(Array(String)))

Delete row

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
# headers can be set as above or later with #set_headers(headers : Array(String))
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"]
]

table.delete_row(1) # => ["2", "Leslie Hutchinson", "1"]

Get row/column

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"],
  ["4", "Lulu Sparkles", "23"]
]

# get row
table[0] # => ["1", "Melody Connolly", "42"]

# get rows
table[1..3] # => [
            #      ["2", "Leslie Hutchinson", "1"],
            #      ["3", "Codey French", "58"],
            #      ["4", "Lulu Sparkles", "23"]
            #    ]

# get column
table["name"] # => ["Melody Connolly", "Leslie Hutchinson", "Codey French"]

Add/remove a column

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"],
]

table.add_column("height", ["158", "163", "189"])

table.remove_column("id") # => ["1", "2", "3"]

Select multiple columns

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"]
]

puts table.select(["name", "age"])

will output

+-------------------+-----+
| name              | age |
+-------------------+-----+
| Melody Connolly   |  42 |
| Leslie Hutchinson |   1 |
| Codey French      |  58 |
+-------------------+-----+

Difference between two tables

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "John Doe", "31"],
  ["2", "Kelly Strong", "20"],
  ["3", "James Hightower", "58"],
  ["4", "Brian Muscle", "3"],
  ["5", "Lulu Sparkles", "28"]
]

other = PrettyTable::Table.new(["id", "name", "age"])
other << [
  ["1", "John Doe", "31"],
  ["2", "Kelly Strong", "20"],
  ["3", "James Hightower", "58"]
]

puts table - other

will output

+----+---------------+-----+
| id | name          | age |
+----+---------------+-----+
|  4 | Brian Muscle  |  42 |
|  5 | Lulu Sparkles |  58 |
+----+---------------+-----+

Sort a table

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "John Doe", "31"],
  ["2", "Kelly Strong", "20"],
  ["3", "James Hightower", "58"],
  ["4", "Brian Muscle", "3"],
  ["5", "Lulu Sparkles", "28"]
]

sorted_table_asc = table.sort("name")
sorted_table_desc = table.sort("name", false)
custom_sort = table.sort { |a, b| a[2] <=> b[2] }

Sorting a table will always return a new table.

To hash

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"]
]

table.to_h # => {
           #      "id" => ["1", "2", "3"],
           #      "name" => ["Melody Connoly", "Leslie Hutchinson", "Codey French"],
           #      "age" => ["42", "1", "58"]
           #    }

To JSON

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
]

table.to_json # => [{"id":"1","name":"Melody Connolly","age":"42"}]

To/From CSV

require "prettytable"

table = PrettyTable::Table.new(["id", "name", "age"])
table << [
  ["1", "Melody Connolly", "42"],
  ["2", "Leslie Hutchinson", "1"],
  ["3", "Codey French", "58"]
]

table.to_csv("./table.csv") # => saves the table to table.csv

# Load table from .csv
loaded_table = PrettyTable::Table.from_csv("./table.csv")
loaded_table.headers # => ["id", "name", "age"]

Contributing

1. Fork it (https://github.com/henrikac/prettytable/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Henrik Christensen - creator and maintainer